A Discussion On Bias

[Rockdiamond]

Date: 7/29/2009 5:19:33 PM
Author: elle_chris

RD- This is a consumer site. Just because vendors, jewelers, appraisers and the like can post doesn''t change that fact. So what exactly are you saying?

HI all,
Personally I enjoy spending time here- and also I have learned a lot.
Is there anything wrong with that?
BTW- I am NOT the one saying it''s a forum for both...have a look at the front page!

 

[elle_chris]

Date: 7/29/2009 6:13:50 PM
Author: Rockdiamond

<b>Date:</b> 7/29/2009 5:19:33 PM
<b>Author:</b> elle_chris







RD- This is a consumer site. Just because vendors, jewelers, appraisers and the like can post doesn't change that fact. So what exactly are you saying?

HI all,
Personally I enjoy spending time here- and also I have learned a lot.
Is there anything wrong with that?



BTW- I am NOT the one saying it's a forum for both...have a look at the front page!

It says consumer advocate site right under Pricescope. Consumers and Vendors are posting for education purposes, no?
You said you felt differently about PS being a 'consumer site". and perhaps i'm being dim, but i still don't understand what a "vendors enjoyment" has to do with your feelings regarding it being consumer site?

 

[Rockdiamond]

Yes it's a consumer advocacy site designed to be used by experts, consumers, and anyone else wishing to participate.
How does that sound?

 

[Allison D.]

Date: 7/29/2009 6:13:50 PM
Author: Rockdiamond






BTW- I am NOT the one saying it's a forum for both...have a look at the front page!

David, it might behoove you to look higher on that same front page.

Pricescope defines itself as a Consumer Advocate site; that's its purpose and mission.

If you go to the bottom of the page and click on the "About", you'll find this:
http://www.pricescope.com/about.asp

All the text talks about helping "you" buy a diamond. Who do you think the "you" is here?

Yep, it's the customer. (Pricescope rightly presumes that the experts already know how to buy diamonds.

)

I also note the portion you pointed to is a hyperlink; I'd presume its function is to help consumers navigate to the place where they can access consumers and experts.

ETA: I don't think anyone is trying to suggest that vendors don't have a place here. I think they are trying to (rightly) say that the mission and purpose of Pricescope is to help consumers make smart diamond purchases, and that shared common purpose should help shape and guide the manner in which we all (consumer and vendors alike) participate here.

 

[elle_chris]

It sounds like you''re still pushing for this to become a vendor site.

 

[Garry H (Cut Nut)]

Date: 7/29/2009 6:26:11 AM
Author: Serg

Date: 7/29/2009 2:53:43 AM
Author: ChunkyCushionLover

Date: 7/28/2009 3:29:30 PM
Author: Serg

CCL,

I like your post very much, I agree with most your statements.
but i disagree with statement what you or any other person can grade Cushion just by numbers( if we are speaking about proportions)
I am working in Cut grading field ( based on 3D model and computer modeling) more than 12 years, I am project leader such projects as Helium scanner, Diamcalc; MSS, ...; I am working on Cushion optimization more than 2 years( you can check last results here www.octonus.com.oct/projects/movies2.phtml).
based on all my experience in this field Nobody could grade Cushion light performance by proportions only. In our research finaly we all times use comparison by human observations. same for round cut with nontraditional proportions.

Serg,

I love the work you are doing and have many questions.
I would like to run some cushion simulations with you based on the the qualitative trends I have seen from top performing cushions.
This is purely from an academic perspective as I am not in any way connected to the diamond business.

I don''t think simulations will be used anytime soon for cut grading in fancy shapes but I would like to see vendors using the simulations to show consumers the approximate look of a stone before they call it in.
I would also use a methodology like this: Vary one or two variables (example: crown height and depth of a stone) and keep the other independant variables fixed and then compare images of faceup appearance simulation under ASET lighting and regular lighting.

I have had the pleasure of being sent a couple of .gem files from one vendor of an unfinished and then a finished stone. The .gem file immediately told me under the ASET lighting what I wanted to know about the optics of the stone and this was confirmed with the real life finished product. The accuracy is not 100% but a lot of information is still available from the renderings.

I may not fully understand the limitations of the reflector technologies and the simulations from numbers but that is expected I haven''t had the training or tools given to me yet.
I do however know that given enough enthusiastic minds working with small contributions on top of one another in academia the problems in Chemistry that were once though impossible to solve have been answered quite comprehensively.

Regards,
CCL

CCL,
In next week i will prepear and publish explanations of main limitations reflector technologies in new tread. I am in forest now and can not download pictures
As.
1) Stereo human vision. For example Tolk. Cut has cross ray traicing what is very important for human stereo vision. Other cut with nice ASET but without cross raytracing will more dark.. Same for BS, ISee2, iMAGEM
2) ETAS distribution. cut could have perfect ASET/IS but just few directions to catch light in notmal view conditions.for example France square
3) Reverse brightness for leakage( P41.2Cr34.5)
4) FIRE. No dispersion in ASET/IS
5) DETAS.
Then I will try answer on your other questions, just write your questions clear please.
I did not find direct questions in your post
Aset/IS is selection and rejection tools. Its are fine for such tasks. But its should not be used as grading tools specialy for fancy cuts

Sergey should we start a new thread for this topic?
I have a lot of the material that could be postedn (unless it is secret)
e.g. the pear shape optimizatin example.

 

[Allison D.]

More simply put: the goal of Pricescope is to help consumers get the information they need to make satisfying and informed diamond choices.

There is nothing in that mission that says there is a dual goal to help vendors increase their business, but common sense dictates that it will be a likely by-product for those vendors who meaningfully and pleasantly contribute to the community in a positive way.

(slang: win-win situation)

 

[Rockdiamond]

Sorry guys- I just noticed the logo after making that post.
It clearly states "Consumer Advocay Site".
It also says Expert and Consumer Forums- hence my confusion.
I apologize.

elle, I wold never want to do anything to inhibit this or any site from being geared toward assisting the consumer.
Altough sometimes it get''s buried in discussion, that''s my motivation for posting.
I can afford to spend time doing so due to the gracious managment of PS who allows us to post the link

if I never made this clear, I''ve run my business in such a manner as to treat others as I would want to be treated.
I''m a large advocate for transparency in the sale of diamonds- and I''ve spent years showing how I do this, brick by brick, or stone by stone, as it were.
I make sure that anyone buying from us knows if there is any issue with anything we''re selling.
I take photos and videos that have proven to be extremely effective at conveying how the thing looks.


SO it kind of hurts to be put in the position of such a bad guy simply because I might go about it in a different manner.

 

[LD]

Date: 7/29/2009 6:47:51 PM
Author: Rockdiamond
Sorry guys- I just noticed the logo after making that post.
It clearly states ''Consumer Advocay Site''.
It also says Expert and Consumer Forums- hence my confusion.
I apologize.

elle, I wold never want to do anything to inhibit this or any site from being geared toward assisting the consumer.
Altough sometimes it get''s buried in discussion, that''s my motivation for posting.
I can afford to spend time doing so due to the gracious managment of PS who allows us to post the link

if I never made this clear, I''ve run my business in such a manner as to treat others as I would want to be treated.
I''m a large advocate for transparency in the sale of diamonds- and I''ve spent years showing how I do this, brick by brick, or stone by stone, as it were.
I make sure that anyone buying from us knows if there is any issue with anything we''re selling.
I take photos and videos that have proven to be extremely effective at conveying how the thing looks.


SO it kind of hurts to be put in the position of such a bad guy simply because I might go about it in a different manner.

David - discussion is the very essence of this forum and by it''s very nature issues will become buried. Sometimes, it''s best to go with the flow and allow things to become buried otherwise there''s a tendancy to be seen to be resurrecting the same old same old same old subject and people lose interest.

If you think the diamond forum is rough to Vendors then honestly you need to take a trip over to the coloured stone forum! Trust me, Vendors get much harsher reviews, even those who are normally the better suppliers! As we don''t have numbers and gizmos to evaluate gemstones, we use our eyes and photographs - very much as you advocate for coloured diamonds - and photos of the worst gemstones in the world, photoshopped pictures and dodgy practices are commonly exposed!

 

[Kaleigh]

I have been a consumer , customer and prosumer. Meaning, I have bought from a bunch of vendors here. After being here almost 5 years, I have learned a lot. Thank you PS. Learning more through distance ed from GIA for a GG..

Now is it wrong of me, after being here a long time to recommend a vendor I haven''t bought from??? I often recommend ERD for cushions. He''s got a great rep here for being the KING of cushions, is he the only one?? Nope, but I recommend him first because I have seen time and time again the amazing cushions he selects. How could I not recommend him?? Answer me that!!!

It''s a serious question to a few of the vendors that feel we shouldn''t recommend them unless we have BOUGHT from them....

 

[Serg]

Date: 7/29/2009 6:40:40 PM
Author: Garry H (Cut Nut)

Date: 7/29/2009 6:26:11 AM
Author: Serg

Date: 7/29/2009 2:53:43 AM
Author: ChunkyCushionLover

Date: 7/28/2009 3:29:30 PM
Author: Serg

CCL,

I like your post very much, I agree with most your statements.
but i disagree with statement what you or any other person can grade Cushion just by numbers( if we are speaking about proportions)
I am working in Cut grading field ( based on 3D model and computer modeling) more than 12 years, I am project leader such projects as Helium scanner, Diamcalc; MSS, ...; I am working on Cushion optimization more than 2 years( you can check last results here www.octonus.com.oct/projects/movies2.phtml).
based on all my experience in this field Nobody could grade Cushion light performance by proportions only. In our research finaly we all times use comparison by human observations. same for round cut with nontraditional proportions.

Serg,

I love the work you are doing and have many questions.
I would like to run some cushion simulations with you based on the the qualitative trends I have seen from top performing cushions.
This is purely from an academic perspective as I am not in any way connected to the diamond business.

I don''t think simulations will be used anytime soon for cut grading in fancy shapes but I would like to see vendors using the simulations to show consumers the approximate look of a stone before they call it in.
I would also use a methodology like this: Vary one or two variables (example: crown height and depth of a stone) and keep the other independant variables fixed and then compare images of faceup appearance simulation under ASET lighting and regular lighting.

I have had the pleasure of being sent a couple of .gem files from one vendor of an unfinished and then a finished stone. The .gem file immediately told me under the ASET lighting what I wanted to know about the optics of the stone and this was confirmed with the real life finished product. The accuracy is not 100% but a lot of information is still available from the renderings.

I may not fully understand the limitations of the reflector technologies and the simulations from numbers but that is expected I haven''t had the training or tools given to me yet.
I do however know that given enough enthusiastic minds working with small contributions on top of one another in academia the problems in Chemistry that were once though impossible to solve have been answered quite comprehensively.

Regards,
CCL

CCL,
In next week i will prepear and publish explanations of main limitations reflector technologies in new tread. I am in forest now and can not download pictures
As.
1) Stereo human vision. For example Tolk. Cut has cross ray traicing what is very important for human stereo vision. Other cut with nice ASET but without cross raytracing will more dark.. Same for BS, ISee2, iMAGEM
2) ETAS distribution. cut could have perfect ASET/IS but just few directions to catch light in notmal view conditions.for example France square
3) Reverse brightness for leakage( P41.2Cr34.5)
4) FIRE. No dispersion in ASET/IS
5) DETAS.
Then I will try answer on your other questions, just write your questions clear please.
I did not find direct questions in your post
Aset/IS is selection and rejection tools. Its are fine for such tasks. But its should not be used as grading tools specialy for fancy cuts

Sergey should we start a new thread for this topic?
I have a lot of the material that could be postedn (unless it is secret)
e.g. the pear shape optimizatin example.

Hi Garry,
Please start. You can publish everything about colorless diamonds except Cushion2 and Cushion1 3D models.

 

[Garry H (Cut Nut)]

Unless Ira or Sergey tell me I am thread jacking - the Cut issues Sergey raised will continue here https://www.pricescope.com/community/threads/what-procedures-to-follow-when-reflectors-cannot-any-longer-help.121388/

 

[Regular Guy]

Date: 7/30/2009 8:19:05 AM
Author: Garry H (Cut Nut)
Unless Ira or Sergey tell me I am thread jacking - the Cut issues Sergey raised will continue here https://www.pricescope.com/community/threads/what-procedures-to-follow-when-reflectors-cannot-any-longer-help.121388/

...and look what I woke up to over there, indeed!

Garry, I''ll respect your selection of that thread, and it''s purported intent, for the continuation of this topic...but (and I will only look more closely at what''s there a little later)...like the CEO for a therapy company who may not know the quantitative detail that needs to go into analysis of success, but who knows enough that you have to look at the bottom line...I read broadly from the bottom line of Sergey''s conclusions that ASET is not sufficient for selection...at least consistent with HCA...and therefore, the intent of that thread was to consider fundamentally what strategies therefore remain, and how to implement those. Although a brief reading of what''s written there now doesn''t go to post ASET (or some kind of consideration of it)...that was my intent.

 

[Black Jade]

Date: 7/29/2009 7:10:00 PM
Author: Kaleigh
I have been a consumer , customer and prosumer. Meaning, I have bought from a bunch of vendors here. After being here almost 5 years, I have learned a lot. Thank you PS. Learning more through distance ed from GIA for a GG..

Now is it wrong of me, after being here a long time to recommend a vendor I haven''t bought from??? I often recommend ERD for cushions. He''s got a great rep here for being the KING of cushions, is he the only one?? Nope, but I recommend him first because I have seen time and time again the amazing cushions he selects. How could I not recommend him?? Answer me that!!!

It''s a serious question to a few of the vendors that feel we shouldn''t recommend them unless we have BOUGHT from them....

Kelly, it is great that you are so conscientious.

Reading this thread recently I am feeling like when I used to teach class, and give warnings about people not doing things, and then invariably, all the conscientious students who were handing in their work, etc. would come running to me, worried, while all the students I was trying to warn paid no attention at all.

My reading of what we have kind of been tweaking and working out in this forum, re: the recommendations that are given to questioners is not that we have come to the conclusion that no one can ever recommend a vendor they haven''t personally used--that doesn''t sound reasonable to me at all. I believe the concerns that were raised were, at first, more about bias as it limits the number of vendors being recommended sometimes down to a ''favored few'' and the stones recommended get narrowed down to only a certain type of stone (and consumers are not then served well because they get the wrong impression about what is out there and get narrowed choice). Later, another issue was raised as it became clear that some people who post on the forum are not very well-liked. Or, shall we say, that they arouse strong feelings, whether positive or negative, in others. The concern was then raised that it might happen that consumers would be steered away from these individuals'' products not because they were inferior or because the vendor was dishonest or because the stone that was being offered was not best for the consumer in that case--but because of someone posting who just simply did not like that individual--but was not upfront and honest about their motivation. (Thus also doing the consumer a disservice, even thought the motivation would be not to harm them, but the disliked vendor. )

Some side issues came up as well, such as a discussion of what expertise actually is, and how far tools that allow ''non-experts'' to give opinions actually can be depended upon--but my impression was the two issues in the paragraph above became the big concerns as the discussion evolved.

I don''t think we have come to an agreement yet about what we can do to resolve those two issues, and I actually doubt that they can really be ''legislated'' effectively by the moderators (at least, the ''legislation'' could not be enforced). The best that can probably done is to get people thinking about what is fair and just so far as these issues are concerned, and thinking before they begin typing on the keyboard (or at least, before pressing the SEND button). We all (or most) of us agree that this is a board for consumers ( I certainly think so), but in this case, fairness to the vendors, as much as possible clearly helps the consumer also to get the best possible, widest choice. I think that a person who wanted to give advice to others on this board (and God BLESS such people for all their time and effort and the way they have educated themselves and all that they have done) would probably be fine if they jsut kept the issues above in mind; honestly disclosed when they thought that they might not know something or that they did not know whether or not a vendor unfamiliar to them might not have the best choice for the poster, talked about ASET images and so forth but perhaps revealed that they are not always infallible, and didn''t recommend vendors they do not like (no one should have to do that) but maybe just kept silent instead of involving a consumer (who didn''t know what was going on) in a personal vendetta. I think the best of the prosumers on Pricescope do all of these things already anyway. It wouldn''t really require stating all of these things (or even any of them) in every post, and of course I may have some things wrong and others may have other ideas on them, but that''s my take on what''s been happening here.

I think many of us have learned a lot through this discussion and one of the things that perhaps really came across is that interpersonal relations are important even when they are not face-to-face. So there are real repercussions involved sometimes when you have offended a lot of people. Even if you are completely in the right (which I don''t think that anyone human is ever COMPLETELY in the right). People cannot easily unentangle their emotions from their decisions, even when they WANT to, and reverberations from one thoughtless remark, or post, can go on for a long, long time. On the other hand, a momentum can get getting which is extremely ugly, and especially when people believe that they are ''hidden'' behind screen names and so on, they can easily become what I can only describe as a lynch mob, out to ''get'' someone that is annoying them and not really sifting whether the punishment is really in line with the ''crime'', or even whether there is an actual crime at all, and not bothering to worry if at least some of the things that are being said without much tact are actulally TRUE, and might be good to consider further. And certainly not realizing that what they do ''on-line'' is not in a virtual world alone, but can have devastating real life repercussions on a real person (as well as on others--the very consumers that they would wish to be helping). By the grace of God, and thanks to some very wise webmasters, and many being willing to pause and reconsider and even apologize when it must have been embarrassing to do so, we have avoided certain things this week which would not have been good for anyone, and would not have been good for the culture of Pricescope. And I think we are on track to all move on, and all keep making this even better that it is (which is already pretty good).

P.S. More full disclosure: I was a very offensive person when I was young, and would go from place to place making enemies and not influencing people and then being confused about it. I have a pretty good brain and I think outside of the box and I was sure I always knew what was best and I would just BLUDGEON people with this. And they didn''t react very well, as you can imagine. This week has brought up a lot of emotions for me as I remember the past and you guys have been REALLY nice to me, really healing--marriage proposals are nice, of course, but being told that I have acquired some tact with age is very healing and reassuring. I think I do still have a lot of tendency to lecture, though, so forgive me if I have done that a little (or a LOT) too much and of course everything I say is (what useful initials these are) JMO.

 

[Rockdiamond]

Black Jade- it would be impossible to overstate your value in this conversation.
You''ve been a peacemaker and introduced reason when it seemed everything was going in the crapper.

Thank you.


About the topic- Bias as it relates to diamonds:
If there are two stones, one AGS0, the other GIA VG cut grade.
One ( the AGS) has a better ASET/IS.

Is it accurate to say the AGS stone is better?


A large part of my motivation in this is that there are people who own stones like the GIA VG.
If, after having compared, they might still choose the "lesser" stone ( "lesser" being based in the parameters commonly used here to say which one is better) what is the cost of saying the AGS stone is "better"?

 

[purrfectpear]

Well, while we''re bandying marriage proposals, let me just go on record as saying if there wasn''t a Mrs. Atlas....

So, this thread is about vendor concerns about PS opinions (aka bias) messing with vendor''s breadbasket. Here''s how I feel on the subject. Someone posts a stone that doesn''t meet the criteria that is often used on PS, and since we don''t have it in hand to view with our very own little peepers, a PS''r might say "hmmmm, I don''t like the numbers, can''t recommend, maybe look for something else".

David (to paraphrase) is concerned because it might be a real beauty in his opinion and you''ve potentially swayed a buyer away from that vendor affecting the vendor''s livelihood.

My opinion is that if there is another diamond out there that has better numbers, at the same or close cost...tough to the vendor who lost the sale and good for the buyer. Let the vendor sell his super-duper "gotta see it in person" diamond to someone who can see it in person. The bottom line is that the buyer did not lose out, the vendor might have lost out. Better a happy buyer, than a buyer who has second thoughts, regrets, or pays shipping & insurance to return if the buyer ends up not agreeing with the vendor''s opinion. Most of the time I see opinions that say "if you can visit the vendor, go do it". Some people don''t live close to WF, GOG, or Rockdiamond either.

Pricescope for the most part is about providing advice, guidelines, rules-of-thumb, opinions, and recommendations to the guy or gal who doesn''t have the diamond in hand. In the end it''s still up to the buyer to weigh the advice/opinions and decide for themselves.

Finally, for the record, anyone who wants to argue the point that Karl is THE MAN when it comes to understanding Asschers, or imply his recommendations shouldn''t be strongly considered, is dead wrong IMO. Breadbasket or not.